Physalis peruviana L. belongs to the Solanaceae family and produces a spherical fruit used to treat various diseases. However, the chemical composition, nutritional characterization, and bioactive properties of the P. peruviana growing in the Andean region of the Atacama Desert have not been conducted so far. The results showed clear differences in the nutritional and bioactive characteristics of the fruits grown in arid environmental conditions, which were comparable to those from countries with a production tradition. The fruits studied showed a higher Ca, Cu, Mn, P, and Zn content and bioactive compounds such as flavonoids and tannins than those reported in the literature. UHPLC was performed to determine the main phenols. Gallic acid was identified as the predominant phenolic compound in this species (303.63 mg/100 g FW), of which to our knowledge no previous study has reported similar concentrations in this species. Moreover, Cape gooseberry extract has antioxidant and antimicrobial activity against Gram-positive and Gram-negative bacteria. Pseudomonas syringae (MIC 0.313 mg/mL and MBC 1.25 mg/mL) was the most susceptible bacterium. Meanwhile, Erwinia rhapontici was the most resistant bacterium (MIC and MIB 5.00 mg/mL). Furthermore, it was found to inhibit α-amylase activity with an IC₅₀ value (39.28 µg/mL) similar to that of acarbose (35.74 µg/mL). These results expand the knowledge of the species cultivated in arid environmental conditions and suggest an alternative for the potential use of this fruit to manage chronic diseases such as diabetes.

Soil microorganisms that inhabit extreme environments have unique metabolic capacities and/or physical structures that allow them to survive in oligotrophic conditions. The bioprospecting of unknown bacteria in the context of current advances in genome mining is fundamental for the discovery of natural products with novel properties or applications. In this study, the plant growth-promoting and biocontrol traits of a Pseudomonas isolated from soil associated with plants from the Atacama Desert were characterized by whole-genome sequencing and in vitro assays. A high-quality genome draft of Pseudomonas sp. isolate C3 was obtained. An automated biosynthetic gene cluster analysis using antiSMASH 6.0 revealed the presence of a cluster of genes for the biosynthesis, regulation, and transport of the metabolite 2,4-diacetylphloroglucinol, which showed a high protein sequence identity (>89%) with a validated orthologous gene cluster from another Pseudomonas. In addition, via an in vitro assay, the biocontrol activity of Pseudomonas sp. isolate C3 against Botrytis cinerea, Monilinia fructicola, Phytium sp., Alternaria sp., Geotrichum candidum, and Fusarium oxysporum was corroborated. Finally, through KofamKOALA, the presence of genes involved in different metabolic pathways of plant growth-promoting traits was identified, which was corroborated by in vitro assays. This study provides information obtained from genomic analyses and culture tools on a bacterial isolate from the Atacama Desert characterized by plant growth-promoting capacities and biocontrol activity.

The Region of Arica and Parinacota (Atacama Desert) offers several unexplored remote sites with unique characteristics that would allow for the formulation of new bioproducts for agriculture. Among them, Jurasi Hot Springs, Polloquere Hot Springs, and Amuyo Lagoons represent a group of open pools fed by thermal water springing from the mountains. Their microbiomes remain unspecified, providing a unique opportunity to characterize the endemic community of these sites and develop new bioproducts for sustainable agriculture. Bacteria were isolated from the sediments of these geothermal sites and characterized by sequencing the 16S rRNA gene, microbiological characterization, and agricultural functional characterization. A total of 57 bacteria were isolated from three geothermal sites north of the Atacama Desert. The sequence analysis showed that the isolates belong to several bacterial genera, including Pantoea, Bacillus, and Pseudomonas, among others. The functional characterization revealed the presence of PGP traits, hydrolytic enzymes, and biocontrol activity against phytopathogenic fungi. These bacteria possess the potential to develop new biobased products for agriculture in arid conditions.

Species of Alternaria (phylum Ascomycota, family Pleosporaceae) are known as serious plant pathogens, causing major losses on a wide range of crops. Alternaria atra (previously known as Ulocladium atrum) can grow as a saprophyte on many hosts and causes Ulocladium blight on potato. It has been reported that it can also be used as a biocontrol agent against Botrytis cinerea. Here, we present a scaffold-level reference genome assembly for A. atra. The assembly contains 43 scaffolds with a total length of 39.62 Mbp, with scaffold N₅₀ of 3,893,166 bp, L₅₀ of 4, and the longest 10 scaffolds containing 89.9% of the assembled data. RNA-sequencing-guided gene prediction using BRAKER resulted in 12,173 protein-coding genes with their functional annotation. This first high-quality reference genome assembly and annotation for A. atra can be used as a resource for studying evolution in the highly complicated Alternaria genus and might help in understanding the mechanisms defining its role as pathogen or biocontrol agent. [ ] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY 4.0 International license .

Oregano from Socoroma (Atacama Desert) is characterized by its unique organoleptic properties and distinctive flavor and it is produced using ancestral pesticide-free agricultural practices performed by the Aymara communities. The cultivation in this zone is carried out under extreme conditions where the standard production of different crops is limited by several environmental factors, including aridity, high concentration of salts, and boron among others. However, oregano plants are associated with microorganisms that mitigate biotic and abiotic stresses present in this site. In this work, the S57 strain (member of the Pseudomonas genus that is closely related to Pseudomonas lini) was isolated from roots of oregano plants, which are grown in soils with high content of non-sodium salts and aluminum. This bacterium stimulates the growth of Micro-Tom tomato plants irrigated with saline-boric water. Moreover, it controls the growth of phytopathogenic fungi Fusarium oxysporum and Botrytis cinerea and the nematode Meloidogyne incognita under saline-boric conditions. Together with the high levels of bacterial biomass (~47 g/L), these results allow the establishment of the bases for developing a potential new agricultural bioproduct useful for arid and semiarid environments where commercial biological products show erratic behavior.

In the extreme north of Chile, the genus Tillandsia L. (Bromeliaceae) is represented by three native species, T. marconae Till & Vitek and T. landbeckii Phil., both of terrestrial atmospheric habit, and T. virescens Ruiz & Pav. of saxicolous habit. There is little information on the foliar structures that allow its establishment in arid environments. Therefore, we studied the leaf anatomy of each of these terrestrial and saxicolous atmospheric species from different altitudinal levels (1000 and 3000 m) in the Arica and Parinacota regions of the Atacama Desert. All populations are monospecific. The study considered scanning electron microscopy, optical microscopy, and the fingernail polish technique. The surface distribution of stomata and trichomes of the species is described. The studied species presented hypostomatic leaves, with anomocytic stomata and peltate trichomes on the abaxial and adaxial sides. Trichomes are formed by a central disc of four equal-sized empty cells, surrounded by a peripheral series of several concentric rings, the innermost of eight, the second of sixteen and the outermost of multiple elongated cells, one cell thick, that form the flexible asymmetric wings. The number of wing cells varies according to the species. Trichomes are evenly arranged in long lanceolate leaf blades with smooth margins.